The invention in the field of component handling and, more particularly, in the unloading of electrical components from supply magazines of the gravity-fed type.
So-called "molded carrier ring" components have a body and a plurality of leads protruding generally coplanarly from the body to a surrounding molded ring. These components are shipped and handled with the ring still attached to the leads in order to provide protection of the leads from bending, breakage, and the like. Just prior to surface mounting of a component onto the substrate of a printed circuit board, the component is presented to a processing station at which, simultaneously, the molded carrier ring is removed and the leads are formed by a punch and die.
Heretofore, gravity fed components have been removed from the bottom of so-called "coin stack" supply tubes by means of an escapement mechanism having two sets of fingers. The sets of fingers of this prior art escapement are situated one above the other so that, upon inserting a supply tube into the escapement, the stack of components drops to the bottom set of fingers. In order to dispense a component from the stack, the bottom set of fingers is opened to release a component and the top set of fingers is moved into interfering relation with the next component of the stack in order to prevent gravity feed of the remainder of the stack.
Generally, in order to prevent loss of components during inversion and loading of the tube into the escapement mechanism, a retainer is attached to a dispensing end of the supply tube and component retaining arms thereof are opened during loading of the retainer and tube into the escapement mechanism so that the components will fall into contact with the bottom set of fingers.
A disadvantage experienced with this prior art is that, during insertion of the tube and retainer into the escapement, the generally flat component packages can tilt while falling from the opened retainer arms to the bottom set of escapement fingers, resulting in one edge of the carrier ring slipping between the bottom fingers and uncontrolled dumping of the whole stack of components through the escapement mechanism.
Thus, it is an object of the instant invention to provide a device by which the components may be dispensed individually from a tube of stacked components, without failure and in a reliable manner.
In another type of prior art escapement mechanism, a blocking plate is situated for the bottom component of the stack to rest upon flatly. During acquisition of a component from the stack, a pocketed device displaces the blocking plate laterally clear of the stack and positions a pocket under the stack for reception of the bottom component. The displaced blocking plate, while so disposed laterally of the stack, limits the closeness with which the dispenser can be situated next to another structure such as an adjoining unloader.
Thus, it is an object of the instant invention to provide a stack unloader which requires less surrounding area for the dispensing mechanism.
Additionally, it is an object of this invention to provide a main frame or table for supporting at least two of the improved unloaders in such a way as to share parts of the main frame and minimize an overall area requirement.
These and other objects of the invention will become more apparent to the artisan upon studying the full disclosure.